Air logic controller and metering pump unit for an apparatus for transferring, pumping and metering liquid chemicals

Abstract

An air logic controller and metering pump unit is provided for an automatic liquid transfer and metering apparatus. Such apparatus is designed for bulk storage, handling and transportation of liquid chemicals and for the safe, precise and metered delivery and transfer of liquid chemicals from a source of chemical bulk storage to the place of end use. One form of apparatus includes a portable liquid transfer tank which is used in conjunction with a stationary wall mounted air logic controller and metering pump module located near the place of end use. Another form of apparatus is a portable self-contained unit where the air logic controller and metering pump module and a compressed air supply tank are mounted above and are connected to the portable liquid transfer tank module. Thus the self-contained unit having its own energy source may be moved to any plant location for precision dispensing of chemicals without the requirement for additional sources of air, electricity, hookups, etc. Further, a method is disclosed for transferring, pumping and metering liquid chemicals.

I claim: 
     
       1. An air controlled liquid dispensing system comprising an air logic controller in combination with an air operated positive displacement metering pump; said metering pump having a cylinder and a reciprocal piston therein for delivering a predetermined measured unit of liquid for each cycle of said piston;   a base plate;   a first pneumatic circuit in said controller including a four-way valve mounted on said base plate having a reciprocal valve element;   air pressure and exhaust conduits and a pair of cylinder conduits connected to said four-way valve and connected to a source of air under pressure and to opposite ends of said cylinder respectively, for alternately introducing and exhausting compressed air at a uniform pressure to said cylinder effecting a plurality of continuous pumping cycles of said piston;   a second pneumatic circuit in said controller including a pair of alternately closeable, normally open flow control valves on said base plate;   flexible conduits respectively interconnecting said flow control valves with said first circuit cylinder conduits and with opposite ends of said four-way valve for alternately and continuously moving its valve element from one control position to the other control position;   a third pneumatic circuit in said controller including a pair of pneumatic predetermining countdown digital counters respectively indicating "units remaining in tank" and "units to be pumped", pre-set to any predetermined number;   additional circuits interconnecting said counters with said first and second pneumatic circuits, for metering and counting the number of cycles of said piston in said cylinder and automatically stopping the pumping action when a predetermined number of measured units is reached;   said third pneumatic circuit including a remote signal port connected into said third circuit and adapted for connection to a remotely activated pressure air signal for delivering air pressure to said second pneumatic circuit for initiating the pumping cycle.   
     
     
       2. The air controlled liquid dispensing system of claim 1, said first pneumatic circuit including in each of its cylinder conduits a one-way inlet check valve and a one-way exhaust valve. 
     
     
       3. The air controlled liquid dispensing system of claim 1, said first pneumatic circuit including a cut-off valve downstream of said air pressure source; a pressure regulator and gauge for pre-setting said air pressure at a value of 40-50 p.s.i., approximately;   a cabinet enclosure mounting said base plate and including a cover panel;   a second pressure regulator and gauge mounted upon said panel for pre-setting said air pressure in said first circuit at 35 to 40 p.s.i., approximately; and   said cabinet housing and enclosing said first, second and third pneumatic circuits.   
     
     
       4. The air controlled liquid dispensing system of claim 3, said digital counters being mounted upon said panel within said cabinet and being visually displayed through said panel. 
     
     
       5. The air controlled liquid dispensing system of claim 3, said first pneumatic circuit including an off-on selector switch valve in said cabinet and mounted upon said panel connecting said air pressure source to said first pneumatic circuit and to said second pneumatic circuit. 
     
     
       6. The air controlled liquid dispensing system of claim 5, said second pneumatic circuit having a normally open start button controlled valve connecting air pressure to said flow control valves and for connecting air pressure to said third pneumatic circuit and to said digital counters. 
     
     
       7. The air controlled liquid dispensing system of claim 6, one of said digital counters successively indicating completion of said predetermined number of cycles for a predetermined number of units to be pumped, interrupting air pressure into said second pneumatic circuit and through one of said flow control valves for automatically stopping said pumping action.   
     
     
       8. The air controlled liquid dispensing system of claim 1, said third pneumatic circuit having a normally closed third flow control valve on said base plate connected to one of said cylinder conduits in said first pneumatic circuit and adapted on opening for connecting pressure air to said first and second flow control valves. 
     
     
       9. The air controlled liquid dispensing system of claim 1, a stop button control valve on said panel connected into said third pneumatic circuit adapted on activation to automatically disconnect pressurized air from one of said flow control valves in said second pneumatic circuit for automatically stopping the pumping action. 
     
     
       10. The air controlled liquid dispensing system defined in claim 1 wherein said controller and said pump are wall mounted. 
     
     
       11. The air controlled liquid dispensing system defined in claim 1 wherein said controller and said pump are mounted on the top wall of a portable liquid transfer tank module.